I'm trying to keep this debate civil.
I see what you're getting at - maintaining tire width while changing wheel width. In that case, yes, the tire contact patch will not change theoretically no matter how wide the wheel you put on it. However, the weight matter doesn't go away. If you take a Protege with 215/40R17 (stock tire diameter for a non-MP3/MSP Protege in 17") on a 17x7 and bump the wheel up to a 17x8 all you are doing is increasing weight (assuming constant wheel "design"). Increase to a 18x8 and you're increasing the wheel weight even more with a slight tire weight reduction by going down to a 215/35R18. My point is, if you can only fit a 215-series tire, why bother fitting a 17x9 wheel? Tire flex can be reduced by running quality tires to the point where being mounted on a 17x7 or a 17x8 won't matter. If that is the case, then what other reason, other than appearance is there to run such wide wheels and stretch tires. I think part of the illusion is going from a stock tire size with aspect ratios usually being 50 or greater to something stretched with a small aspect ratio (40 or lower). Obviously there is improvement, but it is by no means the best "handling" setup.
But you're right, all my knowledge comes from watching racing and discussion matters with the Tech's. All the Grand-Am RX-8's run 18x8 wheels, I believe. I can't remember the tire size but I can tell you there was no stretch and good amount of sidewall. All I'm saying is that if a 19x10 wheel gave them better performance, they would run it.
I see what you're getting at - maintaining tire width while changing wheel width. In that case, yes, the tire contact patch will not change theoretically no matter how wide the wheel you put on it. However, the weight matter doesn't go away. If you take a Protege with 215/40R17 (stock tire diameter for a non-MP3/MSP Protege in 17") on a 17x7 and bump the wheel up to a 17x8 all you are doing is increasing weight (assuming constant wheel "design"). Increase to a 18x8 and you're increasing the wheel weight even more with a slight tire weight reduction by going down to a 215/35R18. My point is, if you can only fit a 215-series tire, why bother fitting a 17x9 wheel? Tire flex can be reduced by running quality tires to the point where being mounted on a 17x7 or a 17x8 won't matter. If that is the case, then what other reason, other than appearance is there to run such wide wheels and stretch tires. I think part of the illusion is going from a stock tire size with aspect ratios usually being 50 or greater to something stretched with a small aspect ratio (40 or lower). Obviously there is improvement, but it is by no means the best "handling" setup.
But you're right, all my knowledge comes from watching racing and discussion matters with the Tech's. All the Grand-Am RX-8's run 18x8 wheels, I believe. I can't remember the tire size but I can tell you there was no stretch and good amount of sidewall. All I'm saying is that if a 19x10 wheel gave them better performance, they would run it.
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